Model YEM313 single phase electronic front board installed active energy meter is a kind of new style single phase two wire active energy meter, it adopts micro-electronics technique, and imported large scale integrate circuit, use advanced technique of digital and SMT techniques, etc. The meter completely accords with relevant technical requirements of class 1 single phase active energy meter stipulated in international standard IEC 62053-21. It can accurately and directly measure 50Hz or 60Hz active energy consumption from single phase AC electricity net, it is used for setting indoor or setting out door directly, and it can display total energy consumption by step motor type impulse register. It has following features: good reliability, small volume, light weight, specious nice appearance, convenient installation, etc.